We propose a continuation of a program of research aimed at the discovery of new tools and tactics for the selective control of insect pests and vectors of disease. In collaboration with pre- and postdoctoral associates the investigation will be carried out on the "tobacco hornworm" (Manduca sexta)--a large leipdopteran that we culture throughout the the year on a synthetic diet. Our central objective is to obtain detailed knowledge of the interactions of the brain, the prothoracic glands, and corpora allata in the hormonal control of insect growth and metamorpohsis. Improved understanding of the normal mechanisms may reveal weak spots in the physiological armor of insect pests and vectors of disease.